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dcs question

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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Aug 17, 2002

i recently experienced a situation which is still a bit of a mystery to me. i though about it a good deal and discussed it with my dive buddies, but without a good explanation:
after 12 days of daily diving, doing 1 dive session of 1-1 1/2 hrs per day, with an average of 4 dives between 30 and 50m, i had some symptoms after my 2 last diving days.

the symptoms started after the dive and were: strange fuzzy feeling in the whole body which increased in intensity with exercise and being vertical. a minor headache located somewhere behind my eyeballs. a noticable lack of concentration with a rather concerning disability to read/speak sensibly. all that lasted for roughly 2 hours after the dive sessions. overall i felt rather weak and when walking my sense of balance was a bit challanged.

so my questions are:
1. what are chances that this might be dcs related?
1.1. i know that my depths are moderate plus there are few dives a day, but is there any sort of theory on how n2 saturates over multiple days which then increases a dcs risk on shallow dives?
2. another theory i was presented with was that this might have been related to sea-sickness since on those 2 days the sea was a bit choppy.
2.2.i remember being sea-sick before, but that was a rather messy business. plus my synptoms started after the end of the last dive. before i was feeling o.k.
3. any theories on some delayed n2 narcosis? bevan mentioned that e.f. has posted something about this once.

right now i change my diving to warm-up dives of 10m max, 1 deep attempt only, diving every 2nd day.

this whole thing is a bit of a bummer, really. any plausible explanation is highly appreciated.

thanx in advance


Were you well hydrated on the last day and nourished?

We had a fellow come up for a day of diving, and after 1.5 hours in the water and dives no deeper than 8m, he got extremely sick, very similar to what you describe, and eventually vomitted. After that, lots of water, and some food, he was fine.

He had not drank much water that day and had eaten only a muffin or two. We strongly suspected that was the problem.

Not to say that I would rule out DCS, just another thing to look for.
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Could a CO2 headache be manifested in such a strange way?

From the only 2 times I had a form of sea sickness, Upon returning to shallow water/earth the symptoms disapeared completly without any sign.
Yet I'm not much of a sea-sickness person.

Any chance of foul play by food? or some other sort of mysterious dahabian germ? (asking because I remember you pretended to be dead a few times while I was there.)

I'm not sure how plausible it is that such acute symptoms will disapear only after 2 hours, I guess only a dive docter who saw a lot of cases of DCS can assess that...

Good luck cracking this mystery.
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you did not hang around at 50m for a while
your average depth was ~40m
you spread your dives over more then 45minutes
I doubt this could be DCS (but I ain't no doc).

Other possible reasons I could think of:
too much sun
other disease
awsome! thanks very much for your replies.


on profiles:

i usually do 2-3 20m dives of up to 2:30, some negatives to 9-10m, 1-2 30m pull-ups of around 2:00. then i start with +40m.
intervalls during warm-ups: 2-3 min for 20m dives, 4-5 min for 30m dives, 10-15 min for +40m dives


last food 3-4 hrs before diving, i avoid caffeine before diving and generally drink a lot. i also take various supplements, mostly to compensate mineral deficits here in egypt.


:eek: . no, i wasn't shooting for the bowl from 5m away.
what is a co2 headache?


do you know any symptoms of sea-sickness other than upset stomach, nausea and eventual vomiting? cause that's the only thing i am aware of. still, i was feeling fine until after the last dive.

i checked again some of my dives of the 12 days i mentioned. it all varies pretty much, and there are some days where i would think my n2 uptake was surely greater than what i got on those 2 days that ended with a/m symptoms.
example: one day 4 times 2 min hangs at 30m, another day 5 dives 40-45m with 9-10min intervalls.

2 days ago i did a 40 min warm-up, max 11 m, and one 40m dive only. i regained some confidence, which is already great. i was quite focused on my state of mind during and after the whole dive. i did notice a minor decrease in clearheadedness (i lack a better term) at depth. i would rather blame narcosis for that (on scuba i feel narcosis also relatively early 40-45m). no symptoms whatsoever after surfacing.

i will do similar sessions in the next week and increase depth and will see what happens. or is anyone having another suggestion?

sorry for the long post, but your input is really appreciated.



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Originally posted by immerlustig

:eek: . no, i wasn't shooting for the bowl from 5m away.
what is a co2 headache?
Anyway, you might get a co2 headache after heavy exposure to co2. The only time I got it was after a really heavy modified co2 table (and maybe running), but I hear some people get it from diving as well.
That would just explain a headache though, I can't see how it would be THAT bad.
I was just thorwing options in the air, thought maybe you could link the feeling you had to a more familier yet weaker feeling, and thuss might finding the cause.

Sometimes severe alegies make me feel the way you described... but I'm in serious doubt that there's anything in the sea that you might be alergic to.

I can't seem to think of any plausible reason but DCS, yet no one is sure how likely DCS would be in that case.

Diving more conservativly regarding Nitrogen is the right move, dcs's not something to gamble with, one bubble in the wrong place and you're life might change forever.
After seeing your numbers, I'm now very worried that DCS could be the problem.

From my experience, your profiles on each day (individually) show signs of significant nitrogen retention, although on a one-day basis I would not expect any of those profiles to produce DCS, unless you are 'highly susceptible' to DCS or have PFO.

However, on a MULTI-DAY basis, it is highly possible that you were not 'blowing off' the nitrogen from each day. This also means that it even on 'bad profile' days, you wouldn't necessarily notice DCS symptoms, because you were still in the 'accumulation' phase.

Then, on that last 40m+ dive, the N2 was too much and symptoms hit.

The single most important indicator is that you felt bad suddenly after that dive. Most other problems (sea sickness, dehydration, CO2 headache, etc..) build up gradually.

Eric Fattah
BC, Canada
hi eric

i was also thinking that i might be predisposed to dcs, mainly from years of scuba diving. even though i generally pay great attention to good profiles/ascent rates, there were undoubtly dives where things didn't run smoothly for whatever reason.
that would also be my reasoning why i don't think i got a pfo (i never had it checked, though, but am thinking about it now). if i was predisposed to dcs because of a pfo, then i would assume i should have had some more dramatic experience already. but i'm just guessing here.

i did some further experiments:

27th aug was the last day that ended in my spisode.
28th day off
29th night diving max 15m
30th and 31st mono training max 16m
1st sep: one 40m dive after following warm-up: 6 dives 11m/1:00-1:30 and 4 negatives 7-9m
no symptomes whatsoever
2nd: day off
3rd : fun-diving max 15m/1:00-2:20
4th: one 45m dive after same warm-up
no symptoms whatsoever
5th: day off
6th: one 48m dive after same warm-up.
i had the following symptoms:
i felt light tingling in both hands starting shortly after i finished, which lasted for about 10 minutes. didn't feel at all like a change in circulation which i usually experience after a breath-hold or dive. i remained flat on my back for 1 1/2 hour after the dive and had a feeling of a slowly building up of unwellness. sitting or standing up made me feel slightly worse. after 1 1/2 hrs we drove back home during which time a light headache was developing. concentration and thinking didn't seem to be affected. i went to bed early and woke up with some mild headache remaining which, at the time of typing has disappeared.

are there any suggestions on how long a break is necessary? any info on recoveries of known cases?

i think i'll stop diving more than 10m for at least a week or maybe 2.

anyone any ideas?


I'm real sad to read that some of the symptoms have returned.
I think you should try to advice a hyperbaric doctor, maybe he could insturct you how to do a chamber profile on a line with scuba/nitrox.
Though I don't think many doctors would give free e-mail help to people they don't know.
Maybe contact DAN? do you have some insurance that include those kind of problems? (I really have no clue how freediving is covered).

I can try and get you some numbers/e-mails for Israeli contacts, either at Haifa (hyperbaric medical center) or Eilat (which has a chamber). Or make calls if you can instruct me how to approach this.

Tylerz posted he had been to a chamber recently, maybe he could give you more information about the process.

Is there any chance that smoke/gasoline/tar fumes from the crappy ride to the blue hole caused those symptoms? maybe you exposed yourself to that more than normal lately?

will contact the chamber, and dan covers freediving, so will see what happens there. anyone knows what kind of medical tests could show a dcs case?

there are 2 issues i wonder about more and more: how does a rapid ascent during a freedive affect you? and how does de/saturation develop during repetitive freedives?

i've read posts elsewhere where it was suggested that to be relatively safe one just adds uw-time up until it reaches nodeco time for scuba. that theory seems quite wrong to me, since nodec-times for scuba only go for slow ascent rates, which a freediver never has.
i've so far believed that my earlier mentioned surface intervalls were on the very conservative side, but these days i wonder.
if i do indeed experience dcs-cases (which i believe at the moment) then i obviously need 24-48 hrs to desaturate from 1 dive session. and this includes max 10 dives to 10m plus one dive between 40-50m. rather ridiculous, it seems.
well, in order to find that out i first will need to desaturate totally to start the new series of dives, plus i preferably haven't predisposed myself even more to dcs. that is another big questionmark which someone hopefully can answer.

no bubbles, no troubles...HAHA

anyhow, it's time i improve my dynamics anyway...

unfortunately years of diving without problem does not necessarily mean you don't have a PFO. A friend of mine has been scuba diving full time for 10 years, got bent last year and has just found out he has a 1cm PFO.

Your symptoms do sound a lot like some of the symptoms I had with DCS last year - and sometimes still get after lots of freediving. Hydration seems to make the greatest difference to me together with longer surface intervals (Doc advised 10mins, I usually work with around 6 min)

best of luck

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that's very interesting. but for what depths does your doc recommend 10 min breaks?
when you say you get similar symptoms after lots of freediving, can you describe how much freediving that is?
another question: do you have a pfo? if not, did your dcs history result in earlier/more regular dives with symptoms?
what's your approach to doing deeper dives (how many days a week, dives before max, warm-up depths, surface intervalls etc)?

plus already posted question: what's a suggested desaturation time after a dcs case like mine (unless somebody tells me it's not, in which case i wouldn't be upset about at all)?


the advice I got was 10 mins between any dives below 6m. I worked with this for a few months after the bent but now keep it for any dives below about 20m which seems to keep the symptoms at bay. After the bends I got treated for, I had one month off freediving and six months off scuba.

Now I only scuba dive on nitrox (using air tables) and don't go below 30m

I don't have a PFO and had the test. One theory is that the bend was caused by slight lung damage - I had sustained some lung squeeze competing in Cyprus a few weeks before my accident - but that was never proven and by the time they checked my lungs (six weeks after the bend, 2 months after Cyprus) there was nothing to see.

I get mild symptoms now if I make say more than about 20 dives a day below about 15m. Drinking loads of water and some sleep gets rid of them but I do have my own O2 kit now and use that occasionally after a big day.

The doctors who treated me were at the Diving Diseases Research Centre in Plymouth, UK. They are very interested in freediving. It might be worth contacting them for some advice www.ddrc.org

DAN may also be able to help. I don't think any doctor would recommend in water deco though!


quote "Drinking loads of water and some sleep gets rid of them"

that means you can't prevent them?

a question on recovery: why is such a long period of no diving advised after a dcs case? i know some cases in my neighborhood also where the diver isn't allowed back in water for months. what kind of bubble related damage takes that long to heal? i assume desaturation is finished well earlier. and if the healing process is finished, what is the remaining damage that makes another dcs case more likely to happen?

in your case, if you had recovered properly, then you shouldn't get symptoms after a series of 15m dives, no?

what kind of diving do you do now? i'm especially interested in the warm-up before a max and how many days you dive max, that kind of thing.

i've emailed also the adress you recommended plus 2 other sources and wait for a reply. thanks a lot.

meanwhile i stay dry and ponder a life of half and empty lung dives.


Roland my friend, I would recommend that you speak to DAN and/or a hyperbaric doctor before arriving at a prognosis and then self-medicating. There is no substitute for an actual assessment amigo! The outcome may be better than expected.
Best wishes sidiki,

very true indeed. i already emailed around and will hopefully get some tests done the next week or so.
however, since dcs in freediving is obviously not that common i try to gather as much information as possible.


I had residual nerve and tissue damage - I still do. Hence the long recovery time. It took about 6 months to get full sensation back in my leg and a year before the joint damage healed. (I was misdiagnosed with ligament strain at first so sat around with with some bubbles in my knee joint for rather too long which meant it damaged the tissues, had I been treated quicker, there would not have been such residual damage)

I can now only scuba dive on nitrox, and keep shallow and sensible.

Freediving - well I just try and keep reasonable surface intervals (at least 5 mins) and drink loads. Occasionally I get minor symptoms - mainly tingles, extreme fatigue or a strange kind of brain drain that I now believe is DCS - and if so I drink loads of water, sleep and sometimes hit the oxygen. They go away pretty quick with lots of water


How fast do you ascend during your dives? How fast do you ascend during the last 10-15m? Perhaps a slower ascent in the last 15m might help, or even a short 'deco stop in apnea.'

However, given your profiles, it does seem that you are very susceptible to DCS.

Eric Fattah
BC, Canada
Just read all of the posts and one question comes to mind, are you going to the dive site via a boat, if so, is there the chance of CO build-up any where you are sitting, or exhaust rolling back into the cockpit of the boat? Symptoms sound a lot like CO/CO2 problem since the condition alleviates itself after 24-48 hrs. DCS neurological hits usually don’t clear up that quick. Or, do you smoke? Hope that helps
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